A 1997 American Cancer Society study of more than a million people over seven years examined long-term exposure to soot and its relationship with mortality rates. This month, researchers at the Health Effects Institute announced the results of a reanalysis of that study, which included 11 years of follow up with the original participants.
They found that when they included neighborhood level data such as income and education levels, the risk factor from soot pollution increased significantly. Louisville has struggled with higher-than-advised soot levels, both from vehicle traffic as well as industrial sources.
On the web: Health Effects Institute study